justDIY
Active Member
looking at the datasheet for National LMC555, it seems to indicate it works down to 1.5v ... am I reading this correctly?
I'd like to build a one-shot timer to control lights in an art piece ... push a button, lights come on for N seconds, and then off until the next viewing.
the lights are powered with two AA 1.5v batteries, using a switchmode boost converter (outputting around 22v@25ma). when the batteries are new, the voltage is a little over 3v, however, as time goes by, the switcher sucks the batteries dry, and eventually stops working properly around 1.5v (minimum input for the switcher is 1.8v)
my plan is to use the 555 to control the switchers enable pin, rather than bothering with the added bulk of a switching transistor of some sorts.
is the C555 the best chip for this job, is there something better / smaller / simpler?
oh, how do I figure out what the stand-by current of the 555 is? The switcher draws 1uA while in shutdown, which is probably lower than the self-discharge current of the batteries.
I'd like to build a one-shot timer to control lights in an art piece ... push a button, lights come on for N seconds, and then off until the next viewing.
the lights are powered with two AA 1.5v batteries, using a switchmode boost converter (outputting around 22v@25ma). when the batteries are new, the voltage is a little over 3v, however, as time goes by, the switcher sucks the batteries dry, and eventually stops working properly around 1.5v (minimum input for the switcher is 1.8v)
my plan is to use the 555 to control the switchers enable pin, rather than bothering with the added bulk of a switching transistor of some sorts.
is the C555 the best chip for this job, is there something better / smaller / simpler?
oh, how do I figure out what the stand-by current of the 555 is? The switcher draws 1uA while in shutdown, which is probably lower than the self-discharge current of the batteries.